Spinning device for airplane landing wheels



,March 14, 1950 c. T. SANDS, JR

SPINNING DEVICE FOR AIRPLANE LANDING WHEELS Filed June 27, 1947 INVENTOR. CHARLES 7: SANDS JR. Y/4z0zM/q Patented Mar. 14, 1950 :SPINNING :nEivIcE FFOR maNnmG wvnrzrztys Charles "1-. LSamla, un ns uinore, tMd. swummsmerv.imizseriamo.ism-1a This invention .relates lto vehicular wheels and more particularly to those usable on the landing gear of airplanes.

In .a particular dorm rofxllanding gear sfor air planes, the pneumatic "tired wheels itheretm .for

landing purposes, are .probelledor rotated hill-high speed before landing through mechanism within the airplane, in order to reduce the stresses incurred during landing on the mhniway. Without this rotation the rubber on .theR-tires is apt to be torn off in large pieces during the v:flanding, tend- :ing to cause irreparable damage to the=tires and possible blowouts. This mechanism however is placed on the landing gearyso asato engage the surface of the wheels or .tires so a to rotate them. The position of the mechanism is. usually v:such that it is seriously reflected :by'o'entrifugal force. shocks and other stresses. iAtarspeed-of .100rmiles per hour and .the shock-of :lalndinglon the iumway,

the stress on the mechanism isso great-that it i usually cannot stand it, and .in its break-up .in- .duces considerable induny the; airplane. Even though :in some instances the mechanism :is able to withstand :the stresses several "times, :its even- .tual life is short.

It is therefore :an object-of the imtesent invention to provide a new and improved wheehrctab ,ing mechanism .for the .wheelsmof an airplane landing gear that will avoid one "or more :of the disadvantages and limitations of the prior art.

Another object iorlthls linvzention is ito :provide a new and improved wheel rotating mechanism for the landing gear o f airplanes "that'wiil be self- .contained and. compactandrsosituated-that iit will not be subject to excessive mentrifugal eflects.

Another object of :this {invention ":is to provide a new :and improved wheel-rotating rmechanism for the landing gear of rairplanesi that" willxhave the driving mechanism enclosed within its axle.

other objects'will.becomeapparent as the invention is more fully set forth.

For a. better understanding of .:;the invention and the objects thereof reference-is made to the appended drawings.

features and principles of the invention. This particular 'forrnds used topresentan examples: :the invention andnot to'limitjt,theretofigrihileathe claimsemuh ize'the scopepf .theginventien.

the drawings: s I

Figure 1 isanelevation of part of aglanding gear embodying this invention, portions'- of the structure are broken away to show the interior construction;

:In conjunction with these drawings, the following description illustrates the v 2 Claims. (Cl. 244*2103.)

*Eigure 2 .-is a sectional view taken along line -2; -.2:.o.f Eigurewl;

snares ism-sectional view takenalong theline E i-3 f- Figure Land vEigurefd is an inside view with the housing in vsection of armodification-of the mechanism used in this invention to induce the rotation-of side by SldfiWheels-Of alanding gear.

:TSimilar: reference characters refer to similar parts' lthroughoutthe drawings.

f,-In-.the, drawings, the particular form of the It uctuelincludesapartof a landing gear strut to, :such .part -lacing the lower leg that telescopes into theme-triage casing M that proceeds to the -ajirp1ane-.chassis, not shown. The strut in is hol- 'lo'wiwithla right .angle offshoot bearing arm 12 nrojectedztowards the central portion or hub 13 of ';a pneumatic landing wheel 14. The offshoot armkl'hs'erves asabearingpfor the .hub 13, which can rotate freely .thereon. The hub l3-is of con- Mentional aform, .except in the particular that involves the use of .an annular gear 15 on its internal hub passage L6. The gear 1.51s fastened .in place by .m'eans of screws 1 I.

i ;.The hollow 'arm M has an insidechamber i8 .t'o encase a cylindrical casing ,I 'B which forms a .ztigidly held housing 01 an electrical motor .2 1 #:thati'ais' assembled .and positioned longitudinallywtherein. The motor 2.! is'of conventional designjagiid zhasitsshaft 22 extended into one end .of'ecoupling-23. The-flppositeend of the coupling hasiasshaft 524 -;thatextends into agear reduction set 25 ivithina housing '28. The teeth of the last ggear .21 of the rsetzziengage with the teeth of the .annulargear .115. The shaft M supports a gear r511 iwhich r'otates an idler gear 52, which transmits its rotation toggearsfi and 5 4 which are mounted .on 8.581191: positioned in the housing 26. The .geerailrotates the gear 21 that drives the :anmi'lar ,gedri lj and wheel .14. The shafts .22 and ares-al 'ig ned with the axis of the bearing that supports thelhub t3 Of the wheel. The motor 2:! f gpreventedirom;movingout :of adjustment with dn'the casing-J8 by the plate 21-;andgasket28 which are held-in placeby the screws 29. This .lpLfite r2 located ::at :the brush end .of the motor d hasazcentralopening ac to allow :m it rmwer-te rasecond wheel and=provide .a :plural arrangement of wheels when the Weight of the plane requires it. In this modification shaft 24 2,500,577 LT- :T I;

by springs 82. This unit is normally engaged with; a clutch disc 83 attached to a shaft M which is connected and drives a second wheel 14..- In'ex treme conditions the clutch functions as a slicoupling in case one of the wheels is requiredto revolve faster than the other. The housings and 86 can be slipped in and out of the wheel assemb-ly for repairs and interchange byreleas ing the locking means 88 attached to plate 89.

It is not deemed necessary to illustrate the dc tails of such an arrangement as those skilled in the art can readily appreciate manner in which such could be provided without specific explanation as to how it should be done.

The operation of the mechanism is accom-- plished through the use of a switch or connection either manually or automatically operate when the airplane using the invention approaches a landing field. The mechanism speeds up the wheels until they are at a top predetermined speed so that by the time the landing gear wheels reach the ground they will be rotating milliciently fast to cause the tires to hit the runway atabout the same speed as the airplane is travelling. This eliminates any inertia or scuffing effects and thereby avoids any undue stresses onthe rubber of the tires. This enables the tires and wheels to handle the landing effectively and smoothly. Since the motor and mechanism is axially located, it revolves around its own axis, instead of radially about it. The effect of centrifugal force or any iar or shock on landing is therefore "relatively ineffective as compared with many arrangements, where the motor or mechanism is radially located. The chances of misplacement of these parts are therefore minimized. By having the unit within the axle structure arm keeps the device compact and out of the way, as well as oilfering no additional wind resistance. Also the motor and mechanism is effectively enclosed. The wheel rim 32 of the wheel I4 is mounted on a roller bearing arrangement 33 that reduces its friction and keeps it aligned and forms the hub of the wheel. An axle ring 34 keeps the wheel definitely positioned on the bearing The 1 flange 35 On this arm is surmounted by a cap 36 to keep the hub relatively free from dust.

Another feature of this invention is in the use of the electric motor indicated, not only forgetting the tire and wheel up to speed, but also for its use as a generator if the latter should be re tated higher than normal, and thereby feed back into the electrical source of the airplane. This feeding back, serves to exert a braking effect, as well as make use of the excess energy of the plane that otherwise would be wasted. The connections to the motor run back to the electrical source in a conventional mannenzand therefore are not completed in the drawings;v It see he noted that the mechanism, motorreductionigear, etc., are so arranged that they can be'readily reached for inspection, repair, replacementtoiling or other purpose, as access is provided at-the end of the strut l0 where it is exposed beyond the hub of the wheel.

While but two general forms of the invention are shown in the drawings and described in the specifications it is not desired to limit this application for patent to this particular form, as it is appreciated that other form could be made that would use the-same principles and come within :the scope for the appended claims.

Having thus described the invention, what is claimed is:

1. In combination with an airplane, a landing gear carriage structure with strut and bearing 1 arm extending therefrom, with pneumatic wheels thereonna starter wheel unit comprising a motor positioned in said arm, a mechanism for rotatingthe wheel from inside its hub, said motor and mechanism being aligned with the axis of said arm and" with one another, coupling means for tying the mechanism with said motor, means for adjusting said'motor and mechanism as a unit within said arm, means provided on the hub of said wheel for operational contact with said mechanism while the latter is rotating it, a casing for enclosing said motor and mechanism and emp'laci-ng it in the arm for operational functioning in rigid and predetermined relation therein, said mechanism and hub means consisting of annular*andxreduction gearing for adjusting the operationof said wheel as aforesaid said casing including separate housing for said mechanism to permit its adjustment and placement close but not integral. therewith, said motor being electri after starting and after being grounded and rotated by the airplane running on the ground and thereby'offering resistance to the rotation of the wheels and absorb some of the moving energy of the airplane. 1 .2. In combination with the landing gear structure of an airplane having strut and bearing arm, a-wheel rotating unit,'comprising in combination, a-n'electric motor, a casing for holding said motor in predetermined position in the bearingarm between the strut and the hub of a wheel thereof, an annular gear mounted internally in the hub of the wheelof said structure, a reduction mechanism enclosed in said hub including a. housing aligned" with said casing and engaging said annular gearfor operational actuation thereof, and means for facilitating the ventilation of said motor within the arm and providing access to the motor and mechanism, said motor being energized to rotate the wheel priorto landing of the airplane-and to absorb energy from the wheel after landing,' when the speed of the airplane equals that of the wheel.

- CHARLES T. SANDS, JR.

REFERENCES. CITED The following references are of record in the file of this patent:

' UNITED STATES PATENTS 

